<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style>
			.box{
				width: 100vw;
				height: 100vh;
				border: 1px solid red;
				display: flex;
				/* 横轴 */
				justify-content: center;
				/* 元素排列方式 */
				flex-direction: row-reverse;
				/* 纵轴 */
				align-items: center;
			}
			.item{
				width: 80px;
				height: 80px;
				background-color: blue;
			}
		</style>
	</head>
	<body>
		<div class="box">
			<div class="item">1</div>
			<div class="item">2</div>
			<div class="item">3</div>
		</div>
	</body>
</html>